Bitcoin allows money to be sent anonymously across a peer-to-peer global network, with no intermediaries needed to validate or process transactions. That has made it attractive to those who want to keep their identity secret, including those buying and selling illegal goods and services on the internet.
Besides the feature and technology of Bitcoin, for me the best advantage of it is that many developers/countries/investors/people supporting on it. Meaning, the future of bitcoin is very clear that it will be last forever and it will never fall down of course there are instance that Bitcoin is turning red but it will recover soon since it is the best cryptocurrency in the market today.